how long will my money last

here’s a formula you can type into a spreadsheet to see how long your money will last.

=NPER(4%,yearly_spending,-principal)

for instance, if you spend 100k a year, then a 2m$ principal lasts 41 years. so if you think you’ll live no more than 41 years longer, a 2m$ is all you need.

whereas if you use the standard 4% rule (aka 25x rule), then you need 2.5m$ to retire if you spend 100k.